In nuclear power plants, an ion exchange resin is used for purification of cooling water or treatment of wastewater. The cooling water and the wastewater in the nuclear power plants include a radioactive substance (hereinafter, also referred to as radionuclide). A spent ion exchange resin (hereinafter, also referred to as used ion exchange resin) with such radionuclides adsorbed thereon has relatively high radiation dose. Therefore, it is demanded to change the used ion exchange resin into waste having lower radiation dose and to reduce the amount of radioactive waste having high radiation dose by separating the radionuclide from the used ion exchange resin with the radionuclide adsorbed thereon.
Further, in order to treat industrial wastewater including a heavy metal element for detoxication, the ion exchange resin is used. Adsorbing the heavy metal element in the industrial wastewater on the ion exchange resin results in safer wastewater. It is demanded to separate the heavy metal elements from the used ion exchange resin as many as possible and to reduce the amount of industrial waste including a large amount of heavy metal elements when the used ion exchange resin adsorbing the heavy metals is disposed.